Words to Know about

Cells and the Parts of

the Cells

Key words

A membrane-covered structure that contains all of

the materials necessary for life

Cellsel

HomeostasishO-mE-O-'stA-s&s

The maintenance of

a stable internal environment

Unicellularyü-ni-'sel-y&-l&r

Organisms made from a single cell

Multicellular

Organims made of many cells

ProkaryoticprO-'ka-rE-"Ot/

Describes a cell that does not have a

nucleus or any other membrane-covered

organelles; example: bacteria

Eukaryoticyü-'ker-E-"Ot,

Describes a cell that has a nucleus; examples: animals

and plants

The Chemistry of

Cells

Metabolismm&-'ta-b&-"li-z&m

The combined chemical processes that occur in a cell or living organism

DNA DeoxyriboNucleic Acid; hereditary material that

controls all the activities of a cell, contains the

information to make new cells, and provides

instructions for making proteins

ATP Adenosine

TriPhosphate; molecule that

provides energy for a cell’s activities

Nucleic acidnu-'klE-ik-

A biochemical that stores information

needed to build proteins and other nucleic acids;

made up of subunits called nucleotides

Protein 'prO-"tEn A biochemical that is

composed of amino acids; its functions include regulating chemical

reactions, transporting and storing materials, and providing support

Carbohydrate

• A biochemical composed of one or more simple sugars bonded together that is used as a source of energy and to store energy.

LipidA type of biochemical that does not dissolve in water, including fats

and oils; lipids store energy and make up

cell membranes.

PhospholipidA molecule that forms much of a cell membrane

ChlorophyllThe green chemical

pigment in chloroplasts that

absorbs light energy for

photosynthesis

Organelles

Organelle •Structures within a cell, sometimes surrounded by a membrane

Cytoplasm

•Cellular fluid surrounding a cell’s organelles

Cell membrane

•A phospholipid layer that covers a cell’s surface and acts as a barrier between the inside of a cell and the cell’s environment

Nucleus

•Membrane-covered organelle found in eukaryotic cells that contains a cell’s DNA and serves as a control center for the cell

Mitochondria

•Cell organelles surrounded by two membranes that break down food molecules to make ATP

Ribosome

•A small organelle in cells where proteins are made from amino acids

Endoplasmic reticulum•A membrane-covered cell organelle that produces lipids, breaks down drugs and other substances, and packages proteins for delivery out of the cell

Golgi complex

•The cell organelle that modifies, packages, and transports materials out of the cell

Vacuole

•A large membrane-covered structure found in plant cells that serve as storage containers for water and other liquids; animal cells have small vacuole.

Lysosome

•A special vesicle in cells that digest food particles, wastes and foreign invaders

Vesicle

•A membrane-covered compartment in a eukaryotic cell that forms when part of the cell membrane surrounds an object and pinches off.

Plant organelle

s

Cell wall

•A structure that surrounds the cell membrane of some cells and provides strength and support to the cell membrane; found in plants, and fungi

Chloroplast-

• An organelle found in plant and algae cells where photosynthesis occurs